Nonsmoking apartments still expose kids to smoke

NEW YORK (Reuters Health) - Living in a nonsmoking apartment is no guarantee against the dangers of secondhand smoke, warns a new study that measured a nicotine byproduct in the blood of more than 5,000 children across the U.S.

Researchers found that among children in households where no one smokes -- at least not inside -- those who live in multi-unit complexes were exposed to an average of 45 percent more tobacco smoke than those who lived in detached houses.

The finding builds on growing evidence of secondhand smoke's pervasive presence and health hazards. The results may also light a fire under initiatives to make apartment buildings smoke-free and, combined with evidence from a separate new study, could encourage the use of exposure-mitigating tools such as air filters.

"People need to be aware that the behavior of smokers in one apartment can affect the people living in other units," lead researcher Dr. Karen Wilson, of the University of Rochester, New York, told Reuters Health.

"We're still learning more and more about just how significant the effects of secondhand smoke are and just how small the exposure can be to have an effect," added Wilson.

Tobacco smoke can be stealthy. Even if no one in an apartment smokes, it can find its way in through walls, windows and ventilation systems, note the researchers. The toxins can also hang around in a room long after anyone has lit up, creating so-called "third-hand smoke."

Previous studies have found exposures equivalent to a cigarette a day in some nonsmoking apartments, noted senior author Dr. Jonathan Winickoff of the Massachusetts General Hospital for Children and Harvard Medical School, in Boston.

"I think this current study is the last link in the chain of evidence demonstrating the need for smoke-free buildings," Winickoff told Reuters Health. "It will make it very hard for any landlord or municipality to allow smoking where a child lives, sleeps and breathes."

Wilson pointed to the U.S. Surgeon General's latest report that reiterates there is "no safe level" of exposure to tobacco smoke and implicates smoke in a range of childhood illnesses and infections -- from asthma to sudden infant death syndrome.

In their study, Wilson, Winickoff and their colleagues looked at housing arrangements and evidence of tobacco smoke exposure among 5,002 children between the ages of 6 and 18 whose families participated in the National Health and Nutrition Examination Survey conducted between 2001 and 2006.

Based on blood levels of cotinine, a breakdown product of nicotine, the team found that more than 84 percent of children who lived in nonsmoking apartments had been exposed to tobacco smoke, compared to almost 80 percent of children living in town houses with shared walls and 70 percent of children in detached houses.

Cotinine levels were consistently higher among children in apartments. This difference was most stark among apartment-dwelling white children who had more than double the evidence of exposure in their blood compared to white children in detached houses, report the researchers in the journal Pediatrics.

The effects held after taking into account other factors that may be associated with tobacco smoke exposure such as poverty and age.

Smokers in other units can't take all of the blame, however. Some of the children could have been exposed at day care or friends' homes, note the researchers. Their parents may have also smoked outside and carried residue into the apartment on their clothing.

Regardless, the evidence still points to "significant tobacco-smoke contamination in the air of nonsmoking units of multi-unit housing," according to the researchers.

One strategy to lower harmful exposures is to remove the components of cigarette smoke from the air.

In a preliminary study published in the same issue of Pediatrics, researchers found that high-efficiency particulate-arresting (HEPA) air cleaners reduced unscheduled asthma visits among children exposed to secondhand smoke by nearly 20 percent. The devices also appeared to cut down on the fine particles associated with tobacco smoke, although blood cotinine levels and parents' assessments of their children's symptoms remained unaffected.

Lead researcher Dr. Bruce Lanphear of Simon Fraser University in Vancouver, British Columbia, noted that the results combined with those of other asthma studies point to the health benefits of decreasing indoor pollutants.

"Interventions to reduce environmental triggers should become part of the routine management of asthma," he told Reuters Health in an e-mail. "The primary -- and ultimate -- solution is to ban smoking in homes and buildings with children."

Home HEPA air purifiers are widely available, at prices ranging from $100 to well over $1,000.

"I think HEPA air cleaners could play a role in a strategy to reduce indoor exposures to pollutants associated with secondhand smoke," said Gary Adamkiewicz of the Harvard School of Public Health, in Boston.

"But the first approach anyone should take when trying to improve indoor air quality is to look for ways to eliminate the source," added Adamkiewicz, who was not involved in either new study.

Over the last few years grassroots groups and federal agencies, including the U.S. Department of Housing and Urban Development, have been pushing for public and private apartment buildings to go smoke-free.

While only about 5 percent of public housing across the U.S. is currently smoke-free, according to Winickoff, he foresees the number rapidly rising. The Boston Housing Authority, for one, will join the list starting in 2011.

"I believe that landlords and building owners will now be deciding how soon to go smoke-free, not whether to go smoke-free," said Winickoff.

He highlighted the additional benefits for making this move, from enhanced property values to reduced fire risks and clean-up costs between tenants.

Of course, such change does not come without controversy. Winickoff also noted the importance of providing access to the best available resources to help smokers quit in the context of their building going smoke-free. There are, for example, free quit lines available in all 50 states.

"We already protect bartenders and waitresses and flight attendants in their places of work," added Wilson. "Many of these children are home all day long, especially the very young ones, and they don't have any voice or choice in whether they are exposed. We need to think about how to protect them too."